#include<iostream>

namespace zhz
{
	int i = 20;
	double j = 5.5;
	int x = 5;
}

int add(int x , int y = 20)
{
	return x + y;
}
double add(double x, double y)
{
	return x+y;
}

void swap(int& x, int& y)
{
	int tmp = x;
	x = y;
	y = tmp;
}


using std::cout;
using std::endl;

int main()
{
	/*std::cin >> zhz::i;
	std::cout << zhz::i << " "<< zhz::j << std::endl;*/

	/*double sum = add(100);
	cout << sum << endl;*/

	swap(zhz::i, zhz::x);
	cout << zhz::i << " " << zhz::x << endl;




	return 0;
}
